can ispconfig account tables become corrupted?

I am new to ispconfig and have run into an issue with one email account. I cannot add aliases to the account be cause ispconfig believes the alias to be in use. ISPconfig also thinks the account name and email address are in use. Is there a table that keeps the account names and aliases that could have become corrupted?

All of our email accounts are last(5)first(2) so Dave Thomas would be [email protected] for example. Ispconfig does not show dave.thomas thomada or davethomas in use as accounts, email addresses, or aliases, but I cannot use any of them. When I try to create the account or add aliases ispconfig gives me an error that they are already in use.

I have two open threads right now and I think both were resolved in one swift move:

I mentioned before we use a co-domain. When I switched the domain from domain1.com to domain2.com on the basis tab in the web interface, all my problems went away. The catchall was moved to the correct account, all the aliases and bad email accounts started working, and I just might be able to spend the weekend at home instead of the office!

So....what does this mean? Should I keep this method in my back pocket as a "fix all"? What does ispconfig do to the user tables and db files when you swap the main domain in a co-domain configuration?